The Porsche in which British Supercup racer Sean Edwards died was found to have worn brake pads, the opening day of a four-day inquest in Brisbane has revealed.

Edwards was in the passenger seat instructing 20-year-old Will Holzheimer when the car ploughed into barriers and burst into flames at Queensland Raceway on October 15, 2013.

According to an AAP report, police mechanic Sergeant Bradley Dieckmann said the Porsche’s pads were worn down to the replacement level for a racing car.

“In this case the brake pads are that thin they can’t dissipate the heat,” he told the inquest.

Onboard video footage had shown Holzheimer pumping the brake pedal hard before the crash.

The car, a 2004 Porsche 996 GT3 Cup, was on its 13th lap of the circuit when the accident occurred.

The investigation has ruled out previous speculation that a sticking throttle was to blame.

Edwards was the son of former F1 driver Guy Edwards, who was responsible for pulling Niki Lauda out of his Ferrari which erupted in a fireball at the Nurburgring in 1976.

Sean Edwards died from severe head, pelvic and limb injuries which resulted in likely brain injury and significant blood loss.

Holzheimer, who suffered significant injuries in the accident, is scheduled to give evidence later this week.

The inquest continues tomorrow.